Primary Retroperitoneal Amyloidosis: A Rare Cause of Uropathy Obstructive

Abstract

Retroperitoneal amyloidosis, one of the rarest forms of amyloidosis, is characterized by the deposition of insoluble fibrillar proteins in the retroperitoneum. It typically presents on CT and MRI as a soft-tissue thickening or mass with progressive calcification, carrying a risk of obstructive uropathy. The imaging characteristics of retroperitoneal amyloidosis may be similar to other conditions, such as retroperitoneal fibrosis, making image-guided biopsy and histologic evaluation crucial for a definitive diagnosis. This article presents the case of an 81-year-old man with hydronephrosis caused by primary retroperitoneal amyloidosis, an uncommon complication of this rare disease.